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J Neurol Neurosurg Psychiatry. Nov 1995; 59(5): 499–506.
PMCID: PMC1073712

Abnormal refractoriness in patients with Parkinson's disease after brief withdrawal of levodopa treatment.


Two pairwise matched groups of patients with mild to moderate Parkinson's disease and a group of normal age matched controls were used to investigate the effects on simple and choice reaction time (RT) of brief withdrawal of levodopa therapy. Comparisons within and across these groups disclosed a selective effect of levodopa withdrawal. After about 12 hours of levodopa deprivation, patients exhibited an exaggeration of normal refractoriness, the well established tendency for RT to increase progressively as the delay between a response and the next imperative signal is reduced below 0.5 s. Increased refractoriness was at least as great for simple as choice RT. Choice RT on trials involving repetition (as opposed to alternation) of the previous response, however, showed no tendency towards greater impairment by brevity of the recovery period or by withdrawal of medication, eliminating an effector based account. With longer recovery periods, RT was unaffected by medication; indeed, unmedicated patients were as fast as normal subjects under these conditions. Even at the briefest delays, fully medicated patients did not differ from normal controls. The paper concludes with a critical review of chronometric studies of medication effects in Parkinson's disease.

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  • Rafal RD, Posner MI, Walker JA, Friedrich FJ. Cognition and the basal ganglia. Separating mental and motor components of performance in Parkinson's disease. Brain. 1984 Dec;107(Pt 4):1083–1094. [PubMed]
  • Girotti F, Carella F, Grassi MP, Soliveri P, Marano R, Caraceni T. Motor and cognitive performances of parkinsonian patients in the on and off phases of the disease. J Neurol Neurosurg Psychiatry. 1986 Jun;49(6):657–660. [PMC free article] [PubMed]
  • Viallet F, Massion J, Massarino R, Khalil R. Performance of a bimanual load-lifting task by parkinsonian patients. J Neurol Neurosurg Psychiatry. 1987 Oct;50(10):1274–1283. [PMC free article] [PubMed]
  • Pullman SL, Watts RL, Juncos JL, Chase TN, Sanes JN. Dopaminergic effects on simple and choice reaction time performance in Parkinson's disease. Neurology. 1988 Feb;38(2):249–254. [PubMed]
  • Starkstein SE, Leiguarda R. Neuropsychological correlates of brain atrophy in Parkinson's disease: a CT-scan study. Mov Disord. 1993;8(1):51–55. [PubMed]
  • Montgomery EB, Jr, Nuessen J. The movement speed/accuracy operator in Parkinson's disease. Neurology. 1990 Feb;40(2):269–272. [PubMed]
  • Pullman SL, Watts RL, Juncos JL, Sanes JN. Movement amplitude choice reaction time performance in Parkinson's disease may be independent of dopaminergic status. J Neurol Neurosurg Psychiatry. 1990 Apr;53(4):279–283. [PMC free article] [PubMed]
  • Jordan N, Sagar HJ, Cooper JA. Cognitive components of reaction time in Parkinson's disease. J Neurol Neurosurg Psychiatry. 1992 Aug;55(8):658–664. [PMC free article] [PubMed]
  • Jahanshahi M, Brown RG, Marsden CD. The effect of withdrawal of dopaminergic medication on simple and choice reaction time and the use of advance information in Parkinson's disease. J Neurol Neurosurg Psychiatry. 1992 Dec;55(12):1168–1176. [PMC free article] [PubMed]
  • Brown VJ, Schwarz U, Bowman EM, Fuhr P, Robinson DL, Hallett M. Dopamine dependent reaction time deficits in patients with Parkinson's disease are task specific. Neuropsychologia. 1993 May;31(5):459–469. [PubMed]
  • Benecke R, Rothwell JC, Dick JP, Day BL, Marsden CD. Simple and complex movements off and on treatment in patients with Parkinson's disease. J Neurol Neurosurg Psychiatry. 1987 Mar;50(3):296–303. [PMC free article] [PubMed]
  • Welford AT. Single-channel operation in the brain. Acta Psychol (Amst) 1967;27:5–22. [PubMed]
  • Pascual-Leone A, Valls-Solé J, Brasil-Neto JP, Cohen LG, Hallett M. Akinesia in Parkinson's disease. I. Shortening of simple reaction time with focal, single-pulse transcranial magnetic stimulation. Neurology. 1994 May;44(5):884–891. [PubMed]
  • Pascual-Leone A, Valls-Solé J, Brasil-Neto JP, Cammarota A, Grafman J, Hallett M. Akinesia in Parkinson's disease. II. Effects of subthreshold repetitive transcranial motor cortex stimulation. Neurology. 1994 May;44(5):892–898. [PubMed]
  • Zimmermann P, Sprengelmeyer R, Fimm B, Wallesch CW. Cognitive slowing in decision tasks in early and advanced Parkinson's disease. Brain Cogn. 1992 Jan;18(1):60–69. [PubMed]
  • Revonsuo A, Portin R, Koivikko L, Rinne JO, Rinne UK. Slowing of information processing in Parkinson's disease. Brain Cogn. 1993 Jan;21(1):87–110. [PubMed]
  • Mason ST, Fibiger HC. Noradrenaline and selective attention. Life Sci. 1979 Dec 3;25(23):1949–1956. [PubMed]
  • Stern Y, Mayeux R, Côté L. Reaction time and vigilance in Parkinson's disease. Possible role of altered norepinephrine metabolism. Arch Neurol. 1984 Oct;41(10):1086–1089. [PubMed]

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